Presently, one concern regarding Internet Protocol (IP) telephony is the need for seamless integration with a public switched telephone network (PSTN). Because several different signaling protocols are currently being utilized to access the PSTN, it is important for any integrated solution to be able to support all of the various protocols. In general, it may be useful to have one unifying identifier number tied to all of the services (e.g., phone call, electronic mail, web, etc.) that may be used to establish contact with a given subscriber. For example, an E.164 number, which is defined by ITU-T standards, may be designated as a unifying identifier number. An E.164 number is commonly used in E.164 telephone number mapping (ENUM) systems that associate the E.164 number to a number of URI addresses through which a called party subscriber may be contacted.
ENUM systems typically utilize DNS queries to obtain translation data (i.e., URI addresses) for a given dialed number (i.e., the unifying identifier number). As new services are added (e.g., text messages, voice messages, video, IMS communications, etc.), the number of DNS queries thattraverse the IP network will also increase. Also, as the number of services are expanded, the number of URI addresses utilized by subscribers will continue to grow, and thus, will be included in response messages. Consequently, one problem that arises is that a message generated in response to a query message may include more services (both in number and service type) than the query initiator desires. For example, a query initiator may desire only mailto URI addresses because the calling party may only be able to communicate via electronic mail. In this scenario, including URI addresses related to other services in the response message(s) is not needed and therefore unnecessarily consumes network resources. Thus, it would be ideal to limit the response message content in order to decrease the overall bandwidth utilized for transmitting the response.
Accordingly, there exists a need for improved methods, systems, and computer program products for specifying an ENUM service type in a communications network that utilizes a plurality of different ENUM service types.